The present invention relates to an electrical continuity inspection unit for a connector, which has an engagement structure consisting of a resilient locking finger and a finger deflection inspecting pin. The locking finger is provided in a terminal accommodation chamber defined in a connector housing for locking a terminal received in the terminal accommodation chamber. The finger deflection inspecting pin is provided in the connector continuity inspection unit for inspecting an incomplete insertion state of the terminal.
Referring to FIG. 7 or 8, a connector continuity inspection unit 1 has a frame 2 provided with a connector holding portion 4 having a pair of guide posts for receiving a connector 3. The inspection unit 1 also has an inspection part 5 moving forward and backward relative to the connector holding portion 4. The inspection part 5 includes a hollow, rectangular extended main body 6. The extended main body 6 is provided with a plurality of continuity sensing pins 8 each contacting one of terminals 7 arranged in the connector 3. The extended main body 6 is also provided with a plurality of finger deflection inspecting pins 9 each for sensing an incomplete state of one of the terminals 7. Each continuity sensing pin 8 is formed integrally with each finger deflection inspecting pin 9.
Between each continuity sensing pin 8 and each finger deflection inspecting pin 9, there is provided an insulating sleeve 10 secured to the pin by press fit for electrically isolating the pin. The continuity sensing pin 8 is resiliently urged by a coil spring 11 toward the connector holding portion 4.
The connector holding portion 4 is fixed on the frame 2, and the extended main body 6 slides on the frame 2 through a link (not shown) by pivoting a lever 12.
In FIG. 7, the connector 3 is inserted downward into the connector holding portion 4, and the counterclockwise pivoting of the lever 12 moves the extended main body 6 toward the connector 3. Thereby, as illustrated in FIG. 8, a fore half of the connector 3 is received in the extended main body 6, so that the leading end of the continuity sensing pin 8 abuts against an end of the terminal 7. The terminal 7 is connected to an electrical wire 13 (see FIG. 7), and the continuity sensing pin 8 is connected to another electrical wire 14 (see FIG. 7). The wires are connected to a checker (not shown) so that the lightening of a lamp (not shown) of the checker indicates the electrical continuity of the terminal 7.
Meanwhile, an upper terminal 7a of FIG. 8 is incompletely inserted into a terminal accommodation chamber 16 of a connector housing 15. In this state, the connector housing 15 has a locking finger 17 which has been deflecting in a deflection space 18 of the connector housing 15, and the leading end of the finger deflection inspecting pin 9 abuts against a fore end portion of the locking finger 17 so that the continuity sensing pin 8 can not move further forward. Thereby, the terminal 7a is spaced from the continuity sensing pin 8, detecting electrical discontinuity of the terminal 7a to know incomplete insertion of the terminal 7a. 
It is noted that, in the above prior art, there is a possibility of misalignment of the finger deflection inspecting pin 9 with the locking finger 17 when the leading end of the finger deflection inspecting pin 9 should abut against the fore end of the locking finger 17. That is because the finger deflection inspecting pin 9 may swing in an arrow direction P or Q and the locking finger 17 may swing in an arrow direction R or S, as illustrated in FIG. 9, during the engagement of thereof. The dynamic engagement force may further move the finger deflection inspecting pin 9 in the arrow direction P or Q. Thereby, even an incompletely inserted terminal like the terminal 7a may be wrongly determined to be in a normal state due to the electrical continuity of the terminal.
Note that the misalignment is also caused by dimensional tolerances of the positioning of the locking finger 17 and the size of the terminal 7.
In view of the above disadvantage, an object of the present invention is to provide an electrical continuity inspection unit for a connector, which has an engagement structure of a locking finger disposed in a connector and a finger deflection inspecting pin of a connector continuity inspection unit for reliably inspecting an incomplete insertion state of a terminal.
For achieving the object, an electrical continuity inspection unit for a connector has an engagement structure of a resilient locking finger and a finger deflection inspecting pin according to the present invention. The locking finger is provided in a terminal accommodation chamber defined in a connector housing for locking a terminal received in the terminal accommodation chamber. The finger deflection inspecting pin is provided in a connector continuity inspection unit for inspecting an incomplete insertion state of the terminal. The finger deflection inspecting pin has a forward end portion with a concave surface, and the locking finger has an extended forward end portion progressively smaller in section. The concave surface guides and engages with the extended forward end portion.
Preferably, the concave surface has a U-shaped section.
In the present invention described above, the leading end of the finger deflection inspecting pin surely abuts against the fore end of the locking finger, since the locking finger has been deflecting in the terminal accommodation chamber when the terminal is incompletely inserted into the terminal accommodation chamber of the connector housing. That is because the extended forward end portion of the locking finger is guided by and engages with the concave surface of the finger deflection inspecting pin.
The finger deflection inspecting pin does not disengage from the fore end of the locking finger even when the finger deflection inspecting pin tends to swing due to the dynamic abutting force between the finger deflection inspecting pin and the locking finger. That is because the extended forward end portion has been caught by the concave surface. Even with dimensional tolerances of the positioning of the locking finger and the size of the terminal, the finger deflection inspecting pin does not disengage from the fore end of the locking finger, since the extended forward end portion is caught by the concave surface.
Along the U-shaped concave surface, the extended forward end portion is easily guided. Furthermore, the U-shaped concave surface advantageously provides an elongated guide portion.
Thus, the present invention advantageously serves to reliably detect an incomplete insertion state of the terminal.